Proxy exceptions in 12.04 LTS [duplicate]

How do I setup proxy exceptions under Ubuntu 12.04?

Already tried the proposed solutions for earlier Ubuntu versions and none seem to work. There is no Network Proxy Preferences in 12.04 AFAIK.

System Settings -> Network -> Network Proxy does not offer the possibility to add exceptions.

Is there a file where these settings reside so I can edit them manually and add exceptions (and so the settings are honored by all network apps)?

I would really appreciate any info on this one not already mentioned on earlier answers, as none of theme worked for me. Thanks!

You use either gconf-editor /system/http_proxy/ignore_hosts
or dconf-editor (and manually navigate to system -> http_proxy -> ignore_hosts).

Contrary to what others wrote, there is no need to re-login for changes to take effect.
Moreover, settings done for /system/http_proxy/ignore_hosts also take effect for https.

I had the same issue with 12.04 and the solution given on this thread worked for me.

Thanks nvk, this finally worked for me too, but there is a catch:

In dconf-editor there is a help text that reads something like 'if no configuration for https is given, the proxy server configured for http will be used for https too'. This is not true, at least for Ubuntu 12.04. I had to add the server for all protocols, even being the same one for http, ftp and https. After I did this, and after a logging off and in again, proxies (including exceptions) took effect for all applications.

Still, I think the 'normal' network settings GUI could be made better by the addition of an extra input box for the proxy exceptions in the proxies settings part. I hope to see this in a future Ubuntu update.